You Sleep How You Eat
Our diet has a huge influence on the way our body functions, how we feel throughout the day, and how we sleep during the night.
So far, studies have found that these foods promote sleep:
Milk
Milk has long been associated with sleep in Western cultures. A study conducted more than 80 years ago showed that adults who ate a bowl of milk and cornflakes were able to enjoy more uninterrupted sleep.
Milk is likely to benefit sleep because it contains Melatonin. Melatonin is a hormone secreted naturally by the pineal gland, especially at night, and has been found helpful in inducing and maintaining sleep. In an experiment where commercial milk was replaced with melatonin-rich milk, those who drank the melatonin-rich milk reported better sleep and more energy the following day.
The concentration of melatonin in cow’s milk increases significantly if the cows are milked in darkness, during the night, so try to find ‘night-time milk’ at your grocer if you want to drink milk to help your sleep.
Interestingly, in a sample of 29 respondents, milk fermented with Lactobacillus helveticush also seemed to improve sleep quality and facilitate longer periods of uninterrupted sleep.
Tart Cherries
A study monitoring 15 insomniacs reported that drinking the juice of fresh cherries before bed has been shown to alleviate insomnia, and reduce the time it takes to fall asleep.
A separate experiment also demonstrated that rotating different types of cherry juice each day both significantly increased sleep duration, and reduced the number of awakenings each night.
Kiwi Fruit
In an experiment involving 22 women and 2 men, eating 2 kiwi fruits an hour before bedtime has shown to both improve sleep quality, and well as increase the total time spent asleep. They also fell asleep faster. One reason for this is because Kiwi is a natural source of seratonin, which is a precursor for melatonin.
Valerian
Valerian is a herb that causes drowsiness. The valerian root can act to depress the central nervous system and relax smooth muscle. Essentially, it can be considered a kind of natural sedative. Valerian can be taken in a herbal tea, a supplement, and even added to bath water.
Vitamins, amino and fatty acids
Tryptophan is an amino acid, that is eventually metabolised by the body to become melatonin, which is a molecule that stimulates and encourages sleep.
However, in order for tryptophan to become melatonin, it must follow a specific biochemical pathway:
Tryptophan is first converted into serotonin via an enzyme which requires the presence of vitamin B6 to function. Only once this has happened can the serotonin be converted into melatonin, by another enzyme which requires the presence of omega-3 Fatty acids.
In addition, vitamin B3 suppresses the function of an enzyme that converts tryptophan into other proteins, and thus acts to increase the amount of tryptophan available for conversion to serotonin, and subsequently, melatonin.
So, consuming foods with high concentrations of tryptophan (tofu, lentils, beans, fish, pumpkin seeds, eggs) vitamin B3 (peanuts, mushroom, chicken, turkey) vitamin B6 (pinto beans, tuna, pistachios, turkey), and omega 3 Fatty acids (nuts, fish, seeds) should improve your sleep.
It’s also pertinent to remember that certain foods are bad for you sleep (not just coffee!), but more on that next time!
References and further reading:
Laird D, Drexel H. Experimenting with food and sleep I. Effects of varying types of foods in offsetting sleep disturbances caused by hunger pangs and gastric distress-children and adults. J Am Diet Assoc 1934(10):89–94.
Valtonen M, Niskanen L, Kangas AP, Koskinen T. Effect of melatonin-rich night-time milk on sleep and activity in elderly institutionalized subjects. Nord J Psychiatry 2005;59:217–21.
Yamamura S, Morishima H, Kumano-go T, Suganuma N,Matsumoto H, Adachi H, et al. The effect of Lactobacillus helveticus fermented milk on sleep and health perception in elderly subjects. Eur J Clin Nutr 2009;63:100–5
Pigeon WR, Carr M, Gorman C, Perlis ML. Effects of a tart cherry juice beverage on the sleep of older adults with insomnia: a pilot study. J Med Food 2010;13:579–83.
Garrido M, Paredes SD, Cubero J, Lozano M, Toribio-Delgado AF, Muñoz JL, et al. Jerte Valley cherry-enriched diets improve nocturnal rest and increase 6-sulfatoxymelatonin and total antioxidant capacity in the urine of middle-aged and elderly humans. J Gerontol A Biol Sci Med Sci 2010;65:909–14.
Lin HH, Tsai PS, Fang SC, Liu JF. Effect of kiwifruit consumption on sleep quality in adults with sleep problems. Asia Pac J Clin Nutr 2011;20:169–74.
Peuhkuri, K., Sihvola, N., & Korpela, R. (2012). Diet promotes sleep duration and quality. Nutrition research, 32(5), 309-319.